Charger "upgrade" disappointment

The Schumacher Speed Chargers are pretty similar in looks, but I have discovered that they do not all operate the same way. I'm disappointed in the upgrade I did when my previous one developed a bad fan. I expected too much I suppose. In going from the 12/25 to the 10/30, I was hoping to have a faster charger when I needed it (after all, 30 amps is more than 25!). I was hoping to be able to charge at a lower rate (10 amps is less than 12) when I needed to because it would be better on my smallish batteries. I was wrong on both counts.

My new charger operates in a single 10/30 mode, not two separate modes (10 or 30). I've actually measured the rates with my Whatt Meter and they are a little higher than the rated rates. The charger will start at a 12 amp rate as it checks the battery to see how it is responding. Then ramps up to 34 amps if it thinks it's doing OK. It will stay at the 34 amp rate for 1.5 minutes or so, then taper back down to 12 amps for 2.5 minutes. It probably averages out somewhere around 25 amps because the tapers between the different rates take about 40 seconds to complete. So, overall, I probably get about the same charge out of this unit than I did out of the old one (it measured 31 amps constant into a discharaged battery).

The 6000A is probably smarter and probably will handle most larger batteries better than the 2500A, but since I have a mixture of large and small batteries that I want to use with it, I don't have as much flexibility. I can't put anything smaller than about 65AH on it and set it for 10/30 because it will hit it with too much current. I wish, for example, that I could limit it to 10 amps (or less) when I use the 18AH batteries from the UPS units I just received (more on these later). For a 32AH battery, a rate of 8 amps or so would be ideal for me. While the 2 amp rate is probably better for the battery, it simply takes too long to charge.

Oh well, it will still work well for chaining up several together and doing them all at once if I need them quickly*. And it will certainly work great for when I'm running it off of my generator if my solar arrays aren't getting the sun they need (if I ever get some solar arrays :). I think I'll go hook it to the 1984 Blazer I've had sitting in the street for the last 6 months (because it needs work). I'm sure it could use a little electron boost by now.

*Be sure to wire up all of YOUR batteries with at least TWO Anderson connectors each so you can do this kind of thing whenever you need to.